Tanning apparatus.



PATENTED AUG. 1, 1905.

W. E. SMITH.

- TANNING APPARATUS.

APPLICATION FILED SEPTJS, 1904.

, 2 SHEETS-SHEET 1.

Mi lawman. nnnumnaw-mm Wummnc No. 795,942. PATENTED AUG. 1, 1905. W. R. SMITH.

TANNING APPARATUS. APPLICATION FILED SEPTJS, 1904.

2 SHEETS-SHEET 2.

f a UNITED STATES PATENT OFFICE.

WILLIAM B. SMITH, OF BUFFALO, NEW YORK, ASSIGNOR TO BUFFALO LEATHER COMPANY, OF BUFFALO, NEW YORK, A CORPORATION OF WEST VIRGINIA.

TANNING APPARATUS.

Specification of Letters Patent.

Patented Au 1, 1905.

Application filed September 13, 1904. Serial No. 224,258.

. To all whom, it may concern:

Be it known that I, WILLIAM R. SMITH, of Buifalo, in the county of Erie and State of New York, have invented certain new and I useful Improvements in Tanning Apparatus,

of which the following is a specification.

This invention has for its object to shorten the length of time required for the tannage of hides and skins; and it consists in an improved apparatus which involves the circulation and aeration of the tanning liquid or solution, so that the stock (by which term I shall hereinat'ter allude to the hides and skins being tanned) is subjected to contact with a greater quantity of the tanning agent in a given time than would be possible under the ordinary process, which involves the immersion of the stock in a body of stagnant tanning liquid and the stirring of the stock from time to time. In accordance-with my invention I keep up a continuous flow or circulation of the tanning liquid mixed with air, so that currents of said liquid are constantly impinging against all parts of the stock, the liquid being circulated by being continuously withdrawn from the vat or receptacle at one point and continuously returned to it, mixed with air, at another point.

The invention consists in the improvements, which I will now proceed to describe and claim.

Of the accompanying drawings, forming a part of this specification, Figure 1 represents a perspective view of an apparatus embodying my invention. Fig. 2 represents a plan view of the same. Fig. 3 represents a plan view of a modification.

The same reference characters indicate the same parts in all the figures.

In the drawings, (t represents a vat or receptacle adapted to hold hides and skins and the liquid or solution employed in tanning the same, the said vat being preferably an open wooden tank.

(0' represents an overflow tank or receptacle, located beside the vat a and adapted to receive liquid overflowing from the upper portion of the vat through an outlet a 6 represents a circulating-pump, adapted to draw liquid from the tank a and force it into the vat a, said pump having a suction-pipe Z2 communicating with the tank a and a discharge-pipe b communicating with the vat a. The pump may be of any suitable construction. I have used a rotary pump to good advantage, but may use a reciprocating or other type of pump.

The suction-pipe b of the pump is provided with an air-inlet 6 which is arranged to admit air into the stream of liquid flowing through said pipe, the liquid inducing a flow of air into the pipe. The air mingles with the liquid and passes with it into the pistonchamber of the pump, the mixture of liquid and air being forced through the dischargepipe 6 into the vat. The discharge-pipe is extended into the vat, just above the bottom of the latter, and is provided with numerous small outlets 6, arranged to direct jets of the aerated. liquid into the vat. Preferably the dischargepipe has radiating branches, arranged as shown in the drawings, the outlets of each branch being at one side of the branch, so that the liquid has a gyratory movement in the vat, as indicated by the arrows. The outlets of one or more of the branches may be directed upwardly to cause some of the jets to flow with an upward inclination.

By admitting air into the suction-pipe of the pump I secure the following advantages: First, the air-bubbles mingled with the liquid cause a violent agitation and a rapid upward movement of the liquid and the chemicals carried in solution thereby in the vat, so that the liquid is caused to impinge with greater force on the skins suspended in the vat, the

skins being hung on horizontal barsc, supported in the upper portion of the vat; secondly, the power required to drive the pump is materially reduced by the air admitted to the suction-pipe, for the reason that the quantity of liquid forced into the vat in a given time is less than would be the case if the air were not introduced. The decrease in the quantity of liquid is compensated for, however, by the agitation and increased rapidity of movement of the liquid.

When the apparatus is employed for unhairing skins, the liquid overflowing into the tank a may be strengthened from time to time by the addition of fresh chemicalssuch as lime, arsenic, &c.to compensate for absorption of chemicals by the skins in the vat.

The described apparatus is adapted to complete in one vat the process of unhairing skins without employing a series of vats and transferring the skins from one vat to another, much time and expense being therefore saved.

- clined to cause the liquid to flow from each vat to the tank.

I vclaim 1. An apparatus for treating skins, &c.,

. comprising a vat, a liquid-circulating pump adjacent to the vat, suction and discharge pipes communicating with the pump and with g the bottom portion of the vat, and an airinlet whereby the liquid forced by the pump into the vat is aerated.

2. An apparatus for treating skins, &c., comprising a vat, a liquid-circulating pump adjacent to the vat, suction and discharge pipes communicating with the pump and with the bottom portion of the vat, and an airinlet whereby the liquid forced by the pump into the vat is aerated. said air-inlet having means for regulating the quantity of air admitted.

3. An. apparatus for treating skins, &c., comprising a liquid-retaining vat, a circulating-pump adjacent to the vat, suction and discharge pipes communicating with the pump and with the vat, the said discharge-pipe having radiating branches containing liquid-distributing perforations which are arranged to direct the liquid in an approximately horizontal direction and impart a gyl'atory movement thereto.

4. An apparatus for treating skins, &c., comprising a vat or a series of vats, a liquidstorage tank, a circulating-pump, a suctionpipe connecting the pump with the liquidstorage tank and provided with an air-inlet, and a discharge-pipe connecting the pump with the vat or vats.

In testimony whereof I have aflixed my signature in presence of two witnesses.

WILLIAM R. SMITH.

WVitnesses:

DANIEL W. ALLEN, J. E. VooRHIs. 

